Automatic speed synchronizing mechanism for twin motors



Jan. 25, 1944. 2,339,989

AUTOMATIC PEED SYNCHRONIZING MECHANISM FOR TWIN MOTORS R. H. GLANVILLE ETA L Filed Dec. 26, 1942 2 Sheets-Sheet l INVENTORS ROBERTHGLHNVILLE BY ?'PIIEN Mum FORD ATTORNEY Jan.2s,1944. R. H. GLANWLLE Em 2,339,989

AUTOM QTIC SPEED SYNCHRQNIZING MECHANISM FOR TWIN MOTORS ATTORNEY so e Jan. 25, 1944 au'rom'r'rc srann SYNCHRONIZING MECHANISM non 'rwm Morons Robert 11. Glanville and Stephen Mumford, Seneca Falls, N. Y.,-assirnors to Caleb Smith,

Seneca Falls, N. Y.

Application December 26, 1942, Serial No. 470,138 r 7 Claims.

The invention relates to improvements in automatic speed synchronizing mechanisms for twin motors or engines such, for example, as two marine or aircraft motors of the internal combustion type.

The principal object of the invention is to provide an improved mechanism of simple construction for automatically so controlling the speed of one motor as to maintain it at substantially the speed of another motor, the operation of which is manually controlled.

Other objects of the invention are to provide an automatic speed synchronizer which is operable with a minimum oi friction and shock, which may be readily rendered eflective or inelfective at will, and which includes provisions whereby the speed of both motors may be directly manually controlled or either engine may be operated alone, if desired. without injury to the synchronizer unit or the motors.

A further object of the invention is to provide an improved synchronizer of the type disclosed in United States patents to Moore, No. 2,054,908,

granted September 22, 1936, and Smith, N0.

2,217,971, granted October 15, 1940.

A further object of the invention is to provide in an automatic speed synchronizer an improved governing clutch mechanism.

To the foregoing and other ends which will appear from the following description of the preferred embodiment of the invention illustrated in the accompanying drawings, the invention consists in the features of construction, arrangements of parts and combinations of elements and devices particularly pointed out in the appended claims.

In the accompanying drawings,

Figure 1 is a side elevation of the synchronizer unit.

Figured is an end view of the unit as viewed from the right in Figure 1, showing parts of the connections between the unit and the two gasolene engines or motors with which it is assoclated.

Figure 3 is a vertical sectional view on the line I-tofFisurei.

more particularly the clutch mechanism oi the synchronizer.

The improved synchronizing means is con- 86 der manual control. The construction is such that while the synchronizer is in its effective condition, the following or automatically controlled motor will automatically be caused to operate at substantially the same speed as the leading or manually controlled motor irrespective of the cause of changes of speed of the leading motor. When used in connection with twin gasolene motors or engines, such as twin motors of marine or aircraft power plants, the synchronizer may be connected to operate the manually operable throttle valve or the manually operable carburetor throttle valve of the following motor.

In the drawings an installation is shown for synchronizing twin gasolene motors of ordinary construction, only so much of the installation being shown as is necessary for a clear understanding of the present invention.

In the construction shown in the drawings, the following motor or automaticalw controllable motor ill of two twin gasolene motors of conventional construction has the usual manually opermately on the line 5-5 ofFigure 4 and showing able throttle valve or butterfly valve ii of its carburetor it connected as hereinafter described with the improved automatic speed synchronizer unit. It will be understood that both the motor 10 and its. companion motor, not shown, are equipped with suitable manual control means for starting, stopping and regulating the speed thereof, including a valve II for each motor.

The synchronizing unit includes a housing I3 anchored to a base It fixedly secured to a sultable foundation adjacent the two motors.

The end walls of housing or casing it are provided with bearings II and It for a horizontal rotative shaft ll. One end of this shaft abuts the closed outer end of bearing II and the other end of the shaft protrudes from the casing. Fixed to shaft ll midway the end walls of housing. l3 by means of a suitable pin or key It is a radially extending arm or driver 19 having a reduced end portion of round cross-section upon which-is rotatively journaled and held the planetary or connecting gear or pinion 20 of a diiferential gearing which comprises said pinion and two side gears It in mesh therewith. The hub of each side gear abuts the adjacent end wall of the housing and the adjacent side face of driver arm l9, one of said side gears being rotative on a. sleeve-like cylindrical extension 22 of said arm encircling shaft l1, and the other side gear being rotative on a cylindrical bearing sleeve 23 encircling the shaft i1.

Journaled in the upper portion of the housing adjacent opposite ends of the housing are two parallel short shafts 24, each of which extends horizontally at a right angle to shaft |1 the head, ineach of which recesses (three being employed in the construction shown) is slidably mounted a button or plug 46 preferably formed above said shaft Each of said shafts 24 has fixed thereon a worm gear 25. Journaled in the housing below the shafts 24 are two short shafts 26 extending parallel to and above shaft l1. Each shaft 26 has fixed thereon a worm wheel 21 meshing with the adjacent one of .the worm gears -23, and also has fixed thereon a pinion 23 meshing with the adjacent side gear of the diflerential gearing. The two trains --262123 provide a speed reduction gearing connection between each shaft 24 and the connected side-gear 2| of the differential gearing. Each side gear has an annular set of teeth 23 meshing with the teeth of the pinion 23 and an annular set of teeth 23 meshing with the teeth of the adjacent pinion 23.

The outer end of one of the shafts 24 (the right hand shaft as viewed in Flguresl and 3) is connected by suitable means, such as a fiexible shaft, with the leading engine for rotative driving of said shaft 24 in one direction by-the leading engine, and the other shaft 24 is similarly connected with the following engine for rotative driving of said shaft by that engine in a direction opposite to the direction of rotation of the first-mentioned one of the shafts 24.

Mounted on the protruding end of shaft exteriorly of housing l3 are the two metallic heads 33 and 3| of an electromagnetic slip clutch, said heads having circular peripheries. Head 33 constitutes the armature head of the electromagnetic slip clutch and is fixed to shaft H by a key or pin 32 to rotate with said shaft with one face of said head abutting the outer end of bearing l6 and the other fiat face of said head opposed to the inner face of head 3|. Head 3| is the electromagnet head of the clutch and has an annular recess 33 formed in its inner face. Countersunk in this recess is the annular inductionor field coil of the magnet, the ends of which coilare connected to terminals 35 carried by the head and extending to the outer face thereof. The line wires 33-31 of an electric circuit are connected to these terminals and to the terminals of an electric battery 38 or other source of electric current, the line wire 36 containing a manually operable switch 33 for making and breaking the circuit to energize and de-energize the electromagnet at will. The coil is held or sealed in the recess by a retaining mass 43 of asphalt.

Clutch head 3| is rotative, and also minutely axially slidable, relatively to shaft II. A nut 4| threaded on the outer end of shaft l1, and a washer 42 interposed between said nut and the outer face of head 3|, hold said head on the shaft and limit outward sliding movement of the head away from head 33. Head 3| is further supportedand guided by means of an axial cylindrical recess 43 in its inner face which is maintained in telescopic engagement with a cylindrical hub 44 formed on head 33. To permit regulation of the torque exerted by the magnet or head 3| on the armature or head 33,

of Oilite or other self-lubricating material or composition. Adjusting screws 41 threaded through the head 3| bear against said buttons 43 and are locked in adjusted position by lock nuts 43 threaded on said screws and bearing against the outer face of head 3|. Screws 41 and blocks or buttons 43 limit the approach of head 3| to. head 33 to provide an air gap between the heads. By adjusting the width of the air gap, the torque exerted on head 33 by the magnet 3| can be varied. The screws 41 are so adjusted that the projecting ends of the buttons 43 bear lightly against the fiat opposed face of head 33 when the magnet head 3| is deenergized and are held pressed firmly against said face of head 33 when head 3| is energized.

At its outer face the head 3| is formed with an integral arm 43 which extends radially of shaft l1 and said head. This arm is connected by suitable linkage with the manually operable speed control throttle valve ll of the followin engine I3, which valve is normally urged toward closed position by a return spring 13. The linkage shown comprises an army 5| fixedon the pivot shaft 52 of valve H and normally urged by spring 13 to rock the valve to closed position against valve stops 1|, a horizontal link '53 connecting arm 3| to the normally upstanding arm of a bellcrank 34 which is mounted on a fixed axis 55, and a normally vertical link 53 connected at its upper end to the normally laterally extending arm of the bellcrank 54 and connected at its lower end to the arm 43 to urge said arm 43 to the position shown in full lines ,in the drawings when valve ll of the following engine I3 is fully closed by spring 13.

The electromagnet or driven head 3| of the electromagnetic clutch is conversely rotative about shaft l1 through an are which is sufilcient to permit rocking of throttle valv II from its fully closed to its fully open position or vice versa. Rotation of this head 3| relatively to shaft I1 is limited by two fixed stops on the casing 3 and by two stop means adjustably mounted on said head.

Formed on the casing l3, and projecting laterally therefrom adjacent the periphery of the clutch heads, are two stationary limit stops 53 and 59. Extending intothe head 3| from the periphery thereof is an annular series of threaded holes 63. Two metal blocks GI and 62, each having a pair of spacing ribs 63 on its inner face contacting the periphery of the head 3|, are each held to said head 3| by two clamping bolts 34 threaded into appropriate ones of the holes 33. By selection of the pairs of holes in which the pairs of bolts are threaded, the spacing of the blocks about the periphery of head 3| may be varied to provide rough or approximate adjustments of the arc of oscillation of head 3| and its connected arm 43. Further and more minute final adjustments of this arc may be obtained by adjusting a stop screw 35 which is threaded through a head 3|- formed on block SI for abutment of the fixed stop 53 by one end of said screw when the valve II is fully opened. Stop operation. the speeds of the two motors will screw 85 is locked in its adjusted Position by a lock nutii. The block 62 is formed with a head 82', and a compression spring or yieldable stop 61 has one end thereof suitably anchored or fixed in a recess 68 in head 62* and its other "end protrllding from said head for endwise abutment thereof against fixed stop 59. The stop device 62-82=6'| is so adjusted on head 3| that spring 61 abuts stop 59 in the fully closed P sition of valve II with spring 61 not under compression. Upon rapid return of valve II by its spring, the spring 61 will abut stop 59 and be momentarily compressed to absorb inertia shocks, the link 53 moving relatively to the valve operating arm during momentary. compression and following full extension of spring stop element 61 after valve ll of engine III is fully closedand held closed by spring 10.

The link 53 is connected with operating arm 5| of valve H of the following engine H) in the following manner: The left hand end of said link (as viewed in Figure 2) extends slidably through a slot 12 in a stud 13 held to said arm 5i, and carries an abutment or head H to th left of said stud for engaging the stud to rock the arm 5| in opposition to spring to move valve ii to fully opened position when head 3| is rotated into its limit position determined by stops 5865. The usual manually shiftable pivoted control handle 15 for valve ll of the following en ine Iii is, as shown in Figure 2, preferably connected in a like manner to that Just described to said arm 5|. As shown, said handle 15 has connected thereto one end of a link 16, the other end of which (the left hand end as viewed in Figure 2) extends slidably through a slot 11 in a stud 18 held to arm 5|. Link 18 carries an abutment or head. 19 to the left of stud 18 for engaging said stud to rock the arm 5| in opposition to spring in to open valve variably up to and including full opening of said valve.

The abutments or heads 14 and 19 are held to their respective links to shift therewith, and

preferably each abutment is in the form of a nut' threaded on its associated link, and each said nut is held in adjusted position by a suitable lock nut 80. Each of the slots 12 and 11 has its upper and lower edges flared from each other from a point midway the length of the slot to. prevent cramping of the links engaged in said slots. Arm 5| may be rocked to open valve ll of engine it by pull of either one of the links 53 and 16 without movement of the other one of said links.

The mode of operation of the mechanism will be obvious to those skilled in the art but will be briefly set out. When the two motors whose speeds are to be synchronized are in operation, the described differential gearing will cause the shaft I! to rotate in one direction when the speed of thefollowing motor from any cause exceeds that of the leading motor and to rotate in the opposite direction when the speed of the following motor is less than that of the leading motor, and said gearing will, while th speeds of the motors are equal, hold the shaft l1 against .rotation. The shaft will, when rotated, turn the armature head to rotatively drive the magnet head either to permit spring 10 to move the speed controlling element H of the following motor in speed reducing direction or to cause link 53 to pull arm 5| to move element II in speed increasing direction, dependent upon whether the speed of the following motor is greater or less than that of the leading motor. If the magnet head is maintained energized whileboth motors are in always be maintained substantially equal. Opening of switch 39' de-energizes the magnet head and renders the synchronizer ineffective.

If the magnet head is de-energized, the return spring of the speed controlling valve of the following motor will move said valve to zero speed position, and if this movement is a rapid one,

- tors.

the cushion stop 61 will momentarily compress slightly to absorb the inertia forces of arrest of the head 3| and arm 49.

When the magnet head is maintained de-energized, either or both motors may be put into operation and the speed thereof directly manually controlled by the manually operable speed controlling means of the respective motor or mo- When so operated, the armature head of the clutch may rotate without turning the deenergized magnet head of the clutch since there is substantially no driving torque transmitted from head to head under these conditions due to de-energization of the magnet and to the very small frictional contact area afforded by buttons 46 between the heads and to the fact that the pressure of the contact buttons 48 against the armature head, is reduced when the magnet head is de-energized. Under these conditions, it will be noted that the heads 30 and 3| may be relatively rotated, when required, with very little friction between head 30 and head 3|. In the event of over-rotation of head 3| in valve-closing direction, head I52 will abut stop 59 if spring 61 be compressed wholly into socket 68.

It will be noted that the synchronizing mechanism may be enabled and disabled at will by simply actuating the switch 39, and that said mechanism when disabled is not subject to in jury by friction and will not affect proper operation of either or both motors under direct manual control.

Weclaim:

1. An automatic speed synchronizing mechanism for twin motors each having a manually operable and spring returned element manually shiftable to control its speed of operation, comprising, in combination, a support, a shaft rotatively mounted on the support, a difierential gear train connected with said shaft and connective withr both motors whose speeds are to be synchronized for positive driving of said shaft in one direction or the opposite direction respectively in accordance with any increase or decrease in the speed of one motor over that of the other. an electromagnetic slip clutch having a driving head fixed on said shaft and an opposed driven head mounted on said shaft for rotative and limited axial sliding movement relatively to the shaft and the driving head, the driven head being an electromagnet and the driving head being a metallic armature for coaction with said magnet, a source of current electrically connected with said magnet for energizing the latter, an electric switch manually operable to maintain the source of current electrically connected with or disconnected from the magnet at will, means connecting the magnetic head of 'the clutch with the manually operable speed controlling ele-- a motor, while said magnetic head is maintained energized, and stop means for automatically arresting rotation of said magnetic head by said driven armature head when said manually operable speed controlling element is located in either a zero speed or full speed position of said element.

2. An automatic speed synchronizing mechanism as claimed in claim 1, wherein the armature head of the clutch has a face perpendicular to the shaft and opposed to the magnetic head of the clutch, and the magnetic head of the clutch has a plurality of elements mounted thereon about the shaft for slip bearing engagement with said face of the armature head and adjustable axially of the shaft to maintain different selected air gaps between the clutch heads, whereby the driving torque may be varied at will.

3. An automatic speed synchronizing mechanism as claimed in claim 1, wherein the stop means comprises a pair of fixed stopsmounted on the support in spaced position about the shaft adjacent the clutch, and a pair of stops mounted on the magnetic head of the clutch for'engagement of one thereof with one ofsaid fixed stops when the speed controlling element connected with the magnetic head reaches full speed position and for engagement of theother one thereoi with the remaining fixed stop when said element reaches zero speed position, the last-mentioned stop on the magnetic head being yieldabie under impact with its companion fixed stop, and

' means for holding the second-mentioned pair of stops to the magnetic head of the clutch in variably, spaced relation to each other about the shaft.

4. In an automatic speed synchronizing mechanism for twin motors each having a speed controlling element, the combination of a rotative- 1y mounted shaft, a differential gearing drivable by the motors whose speeds are to be synchronized and connected with said shaft to rotate the latter in onedirection or the other in accordance with an increase or decrease in the speed of one motor .over that of the other motor, an electromagnetic slip clutch having a driving head positively rotated by said shaftand a driven head which is rotative and axially slidable relatively to the shaft and is connected with the speed controlling element of one of the motors for actuation of said element upon converse rotary movements of the drivenhead,stop means electromagnetic clutch energized for automatic synchronization of motor speeds or de-energized for operation of either or both motors under direct manual control.

5. A speed synchronizing mechanism for twin motors each provided with a speed controlling element comprising, in combination, a rotatively mounted electromagnet, stop means for arresting the magnet at each or two oscillated positions of the magnet about its axis, an armature for said magnet mounted for rotation about an axis coincident with that of the magnet, means operable by two motors whose speeds are to be synchronized to maintain said armature stationary when the motors are operating at equal speed and to rotate ,said armature in one direction while the speed of one m0t0r is greater and in the opposite direction when the speed of said motor is less than that of the other motor, said magnet having provision for connecting it with the speed controlling element of one of the motors for controlling the actuation of said element upon oscillation of the magnet.

6. A speed synchronizing mechanism as claimed in claim 5, wherein the stop means compr'.se a pair of stop carriers, means for holding each of said carriers independently of the other to the magnet at either of a plurality of difierent selected points around the circumference of the magnet, a compression spring cushion stop held to one of said carriers, an adjustable screw stop threaded in the other carrier, and fixed stop means with which said spring and screw stops are coactive.

'l. A speed synchronizing mechanism as claimed in claim 5, wherein said magnet is engageable with said armature solely through a-p1urality of small interposed thrust elements equally spaced about the axes of the magnet and armature and carried by one of the latter for adjustment toward and from the other.

- ROBERT H. GLANV'IILE.

STEPHEN MUMIORD. 

